1. Field of the Invention
The present invention relates generally to an image formation apparatus and particularly to an image formation apparatus capable of reducing power consumption, a method of controlling the image formation apparatus, and a storage medium.
2. Description of the Related Art
In view of recent environmental concerns, there have been developed image formation apparatuses controlled to shift to a mode of operation in which the apparatus consumes reduced power when it is not used, i.e., a so called power saving mode.
For example, Japanese Laid-Open Patent Publication No. 2006-171297 describes a multifunctional image processor which counts an operation rate for each function and returns only a device that corresponds to a function having an operation rate equal to or larger than a predetermined value when the image processor returns from a power saving mode or a sleep state.
More specifically, the publication describes that a user enters an instruction to return the image processor from the sleep state, and at the time if the printer has a low operation rate, then, only the scanner is returned from the sleep state while the printer is not. This can prevent an unnecessary device from returning from the sleep state, and thus achieve reduced power consumption.
Furthermore, Japanese Laid-Open Patent Publication No. 2007-81721 describes facsimile multi function peripherals allowing a user to set whether to cut power supplied to an external interface unit in an energy saving mode or a power saving mode. When the user uses the facsimile multi function peripherals without using the external interface unit, the user can set cutting power supplied to the external interface unit and thus prevent an unnecessary device from consuming power.
However, these conventional techniques contemplate reduced power consumption by selecting a device to be returned from a power saving mode or by selecting a device to be prevented from receiving power in a power saving mode, and they do not contemplate reduced power consumption by adjusting a condition for shifting to a power saving mode. In other words, conventional image formation apparatuses are typically controlled to shift to a power saving mode when an instruction is not received for a predetermined period of time to operate an auto document feeder (ADF), a console panel, a scanner, a printer and other function blocks configuring the image formation apparatus, and there does not exist an image formation apparatus which changes a condition for shifting to a power saving mode depending on the apparatus's operating condition and thus more effectively achieves reduced power consumption.